Getting the right exposure is the oldest problem in photography and although modern auto-exposure systems bring you a lot closer, there are still lots of situations where they fail. In these cases, modern digital cameras offer some secret weapons that can save the day. These tools are the LCD finder or Electronic viewfinder, and spot metering -- the ability to measure the exposure for just a small part of the image.

Most point-and-shoot digital cameras have both of these, while the DSLRs have only the spot metering. These examples were shot with my Panasonic DMC-FZ28, which has both.

The first step is to learn to understand and interpret what you see in the camera's viewfinder. If there is any auto-gain setting for the viewfinder, as there is on the FZ28, make sure that you find it and turn it off. It will give misleading results. If your camera has an electronic viewfinder, use this instead of the LCD on the back of the camera, especially when outdoors. Then find where in your camera's menu system you can set the exposure to spot metering. When you do this, some cameras put a little cross in the center of the frame to show where the metering system is aimed.

One last thing. Look at the controls on your camera and see if there is a button to lock the exposure and/or the focus. If there is, make sure that it is set so that it locks the exposure. On the FZ28, this button is on the back of the camera and it's marked AF/AE LOCK. Now we're ready to proceed.

Here's our first example. While strolling through Washington DC, I saw this picturesque streetlight with a tree behind it. Let's try the tools built into the digital camera and see how they can help.

Here's the first try, with the metering set to average out the whole frame. While this works well for most situations, it fails here. The tree in the background looks fine, but the detail in the lamp is burned out. People who shoot raw will tell you that if I had shot raw instead of JPEG, I would have been able to recover the detail from the highlights. This is fantasy. The correct answer is to use the right exposure setting.

The correct way to handle this is to expose for the highlights -- the center of the street light. Set the metering for spot metering. On the FZ28, you'll see a little cross in the center of the frame that shows where the exposure is being measured.

Point this at the center of the lamp and you should see most of the frame go dark, while detail begins to show up in the brighter areas. You can move the camera around until the lighting in the scene looks right in the camera's viewfinder. Now press the exposure lock button to hold the setting while you frame the image for the most pleasing view.

And don't worry about the dark background. We'll fix this later in the computer.

Here, LightZone 3, with its "Relight" tool is used to open the shadows and bring out detail in the trees behind the streetlight.

After final tweaks in LightZone, using the Hue/Saturation tool, there's more detail in the tree behind the streetlight. If necessary, you can add a mask so the streetlight isn't affected while working on the background.

Another quick example. Here the streetlight is reflected in a window. With the camera's metering set to measure the entire image, the window is fine, but the reflection is burned out.

With the camera set to spot metering, the center of the image is first pointed to the reflection of the streetlight. The exposure is locked using the lock button on the back of the camera. While the camera holds this exposure, it's time to reframe the image to show the whole window. The reflection looks about right now, but the rest of the scene is very dark.

Using the Relight tool in in LightZone, the shadows are brought up to show more detail. Final tweaking involved rotating the image slightly to straighten it, cropping to center the window, and adding a little haze for a dream-like quality.

As I said at the beginning, in digital photography you can expose for the highlights and develop for the shadows. A burned out highlight is unrecoverable, but there's always detail hiding in the shadows.

Some cameras, like the DMC-FZ28, with improved image quality at the higher ISOs respond better to this, since boosting the shadow detail is equivalent to boosting the ISO of the film in those areas.

In LightZone, I used the "Relight" tool, since this gives you a quick way to see the shadows. From there, you can tweak and fiddle to get the final picture.

Most of the other photo editing programs have similar tools. If not, you can play with the "Levels" tool to raise the detail in the shadows. The thing to remember is that there's always detail hidden in the shadows, but a burnt-out highlight is forever.

Learning to use spot metering, along with being able to interpret what you see in your camera's electronic viewfinder, and using the button to lock the exposure, will help to guarantee getting the right exposure in all sorts of tricky lighting situations. Use this technique when shooting a picture of the moon or a sunset or a situation where the light is behind your subject. Experiment with these tools and you'll boost the percentage of correctly exposed pictures your digital camera delivers.